Sodium and potassium intake was assessed on the basis of its respective excretion levels in 24 hr urine samples. However, owing to the inconvenience of collection, we evaluated random spot urine for alternative sodium and potassium excretion markers. We included 250 patients who submitted 24 hr- and spot urine for clinical tests. However, 22 patients who showed 24 hr urine creatinine excretion levels <500 mg/day were excluded, because these samples possibly resulted from incomplete urine collection. Moreover, 24 patients were excluded because of their use of diuretics during the urine collection period. We observed significant correlations between 24 hr urine sodium excretion and both the sodium/creatinine (r=0.34, P<0.0001) and the sodium/specific gravity unit (SGU) ratios (r=0.19, P=0.007) in random urine samples. Similarly, 24 hr urine potassium excretion and both the spot urine potassium/creatinine (r=0.47, P<0.0001) and potassium/SGU ratios (r=0.28, P<0.0001) were significantly correlated. Although the estimated sodium/creatinine and potassium/creatinine ratios showed a significant correlation with 24 hr urine sodium and potassium excretion, respectively, further studies are required to develop a spot urine test for individualized monitoring of sodium and potassium excretion.
Biomarkers/urine ; Creatinine/*urine ; Humans ; Hypertension/pathology/urine ; Potassium/*urine ; Sodium/*urine ; Urinalysis ; Urine Specimen Collection

BACKGROUND: Estimates of daily sodium (Na) and potassium (K) excretion were explicitly biased when using equations for adults. We aimed to develop equations to estimate them using overnight urine from Japanese children and adolescents. METHODS: The subjects comprised 70 students aged 10.49-15.76 years: validation group, n = 34; and verification group, n = 36. Each subject performed two operations of overnight spot urine (U RESULTS: In validation, we formulated Na excretion (mg d CONCLUSION We obtained validated equations to estimate daily Na and K excretion with accessible variables such as Na, K, and Cr concentrations of overnight urine, body height and weight, and age for children and adolescents. When using the obtained equations, caution should be paid to small but definite biases and measurement errors.
Adolescent ; Child ; Creatinine/urine* ; Female ; Humans ; Japan ; Male ; Potassium/urine* ; Sodium/urine*

Child ; China ; Humans ; Iodine ; urine ; Sodium Chloride, Dietary

OBJECTIVETo compare the changes of urinary iodine levels among the family members with iodine content of 5 - 150 microg/L in drinking water, before and after non-iodized salt intervention through a field trail study.

METHODSFamily members who routinely drank water with iodine content 5 - 150 microg/L were chosen to substitute non-iodized salt for their current iodized salt for 2 months, and urine samples of the family members were collected for determination of iodine change before and after intervention was carried out.

RESULTSMedian urinary iodine of school children, women with productive age and male adults exceeding 370 microg/L before intervention and the frequency distribution of urinary iodine were all above 70%. Our results revealed that iodine excess exited in three groups of family members. After intervention, all median urinary iodine level seemed to have decreased significantly, and groups with drinking water iodine 5.0 - 99.9 microg/L reduced to adequate or close to adequate while the group that drinking water iodine was 100 - 150 microg/L reached the cut-off point of excessive iodine level (300 microg/L).

CONCLUSIONResults from your study posed the idea that the iodine adequate areas should be defined as the areas with iodine content of 5.0 - 100 microg/L in drinking water, and edible salt not be iodized in these areas. Areas with iodine content of 100 - 150 microg/L in drinking water should be classified as iodine excessive.

Adolescent ; Adult ; Child ; Female ; Humans ; Iodides ; urine ; Iodine ; urine ; Male ; Middle Aged ; Sodium Chloride, Dietary ; urine ; Water Supply ; Young Adult

Objective: To investigate the associations between 24-hour urinary sodium excretion (24hUNaE) and all-cause mortality in adult Northern Chinese population. Methods: Data from this study were derived from the prospective urban and rural epidemiology (PURE) study in north China. Baseline information of all participants were obtained by face to face interview through trained research staffs based on questionnaires, and morning fasting urine samples of participants were collected to estimate 24hUNaE and 24-hour potassium excretion (24hUKE). Multivariable frailty Cox regression models were used to explore the association between 24hUNaE (<3.00, 3.00-3.99, 4.00-4.99, 5.00-5.99 and ≥6 g/d) and all-cause death. Results: A total of 27 310 participants were included in this study. The mean 24hUNaE was (5.84±1.73) g/d. After a median follow-up of 8.8 years, 1 024 participants died (3.7%), including 390 cardiovascular related deaths and 591 non-cardiovascular related deaths. The cause of death of the remaining patients could not be determined. Using 24hUNaE level of 4.00-4.99 g/d as the reference group, after fully adjustment, 24hUNaE ≥6.00 g/d was associated with an increased risk of all-cause death (HR=1.24, 95%CI: 1.02-1.49) and cardiovascular related death (HR=1.39, 95%CI: 1.02-1.88). 24hUNaE<3.00 g/d was associated with increased risk of all-cause mortality (HR=1.38, 95%CI: 0.96-1.99). There was no significant association between 24hUNaE and non-cardiovascular related death. Furthermore, using the combination of 24hUNaE 4.00-4.99 g/d and 24hUKE≥2.11 g/d as the reference group, the highest risk occurred in participants with the combination of low sodium (<3.00 g/d) and low potassium (<2.11 g/d). Conclusion: 24hUNaE equal or higher than 6 g/d or lower than 3 g/d is associated with increased risk of all-cause mortality and cardiovascular related death in Northern Chinese population. Besides, moderate sodium intake in combination with increased potassium intake might reduce the risk of all-cause death.
Humans ; Adult ; Sodium/urine* ; Prospective Studies ; Potassium/urine* ; China/epidemiology* ; Proportional Hazards Models ; Cardiovascular Diseases/epidemiology*

OBJECTIVE: To explore the objective evidence of the corpus biochemical changes in rabbits for postmortem diagnosis of potassium intoxication. METHODS: Rabbits were sacrificed by Infusion of 0.3% KCl at full speed push or 1% KCl at 100 drip/min, respectively, with normal rabbits used as control. Cardiac blood and urine samples were collected before and after potassium infusion to examine the concentrations of various electrolytes (K+, Na+, Ca2+, Mg2+, Cl-, and HCO3-) and to observe the antemortem and postmortem biochemical changes. RESULTS: The mean lethal infusion time in the 0.3%KCl group was longer than that in the 1% KCl group (P = 0.006). The serum concentration of K+ increased while the serum concentrations of Na+, Ca2+, Cl-, and HCO3- decreased after the infusion. There were no statistically significant differences in the whole blood concentration of K+ as well as the serum concentration of Mg2+ between the two groups (P = 0.062). There were statistically significant differences in the concentrations of whole blood K+, as well as serum Na+, Mg2+, and Cl-, but not in the serum K+, Ca2+, and HCO3-. There were no statistically significant differences seen in the urine volumes and the concentrations of all the urine electrolytes between the groups. CONCLUSION Examination of the concentrations of K+ both in the whole blood and serum, as well as Mg2+ in the serum may be helpful for postmortem diagnosis of potassium intoxication.
Animals ; Calcium/urine* ; Electrolytes/urine* ; Forensic Medicine/methods* ; Injections, Intravenous/methods* ; Magnesium/urine* ; Male ; Postmortem Changes ; Potassium/poisoning* ; Potassium Chloride/administration & dosage* ; Rabbits ; Sodium/urine*

AIMTo explore the characteristics of the urinary excretion in the elderly patients and to offer some advice for the prevention and treatment of hyponatremia in the elderly patients.

METHODS42 inpatients aged over 80 were divided into tow groups according to their creatinine clearance rate (CCR). Meanwhile, 24 patients aged 45-59 and 31 patients aged 60-79 were chosen as the control groups. All patients were examined 24h urinary electrolytes and CCR.

RESULTS(1) The CCR in the elderly group was lower than in the middle-aged and old group and the 24 h urinary sodium excretion was accordingly diminished than the two groups. 24 h urinary sodium excretion in CCR abnormal group was also diminished than in CCR normal group. The urinary sodium excretion was not linearly correlate with the CCR in middle-aged group and old group but was linearly correlate in the elderly group. (2) The elderly patients' capability of holding blood sodium and excreting potassium was declined in the CCR normal group. But the urinary excretion of sodium, potassium and phosphonium were all diminished in CCR abnormal group. (3) All patients' sodium intake was higher than the criteria made by China Hypertension Association.

CONCLUSIONTheir urinary sodium excretion is linearly correlate with CCR. Urinary sodium excretion is increased when the elderly patients' renal function is relative normal but when the renal function is severely damaged, urinary sodium excretion is diminished.

Age Factors ; Aged ; Aged, 80 and over ; Calcium ; urine ; Coronary Disease ; urine ; Creatinine ; metabolism ; Humans ; Male ; Middle Aged ; Potassium ; urine ; Sodium ; urine

There has been a long-known association between high dietary sodium intake and hypertension, as well as the increased risk of cardiovascular disease. Reduction of sodium intake is a major challenge for public health. Recently, there have been several controversial large population-based studies regarding the current recommendation for dietary sodium intake. Although these studies were performed in a large population, they aroused controversies because they had a flaw in the study design and methods. In addition, knowledge of the advantages and disadvantages of the methods is essential in order to obtain an accurate estimation of sodium intake. I have reviewed the current literatures on the association between sodium intake and cardiovascular events, as well as the methods for the estimation of sodium intake.
Cardiovascular Diseases ; Hypertension ; Public Health ; Sodium* ; Sodium, Dietary ; Urine Specimen Collection

BACKGROUND AND OBJECTIVES: Salt-taste threshold can influence salt appetite, and is thought to be another marker of sodium intake. Many studies have found an association between sodium intake and blood pressure. The aim of this study was to compare the salt-taste threshold and salt intake between hypertensive and normotensive groups. SUBJECTS AND METHOD: One hundred twenty volunteers (51 men and 69 women) who did not take antihypertensive medications were evaluated. First, a questionnaire, which included questions regarding demographic information and preference of salty taste, was conducted, and 24-hour ambulatory blood pressure was checked. Then salt taste threshold was measured by assessing the ability of the subjects to discern the taste of salt in graded solutions of saline. Lastly, 24-hour urinary sodium was measured in a 24-hour urine collection. RESULTS: The salt taste threshold and taste preference for salt were slightly higher in hypertensive group. There was slightly higher salt intake measured as 24-hour urinary sodium in the hypertensive group, compared with the normotensive group. However, there were no significant differences in salt taste threshold, preference of salty taste, and salt intake between the normotensive and the hypertensive groups. CONCLUSION: The threshold of salt taste was not related to sodium intake and hypertension status. These results suggest that the development of hypertension depends on the complex interaction of factors such as genes and environmental factors rather than sensory factors like taste threshold and taste preference.
Appetite ; Blood Pressure ; Humans ; Hypertension ; Male ; Sodium ; Sodium Chloride ; Taste Threshold* ; Urine Specimen Collection ; Volunteers

OBJECTIVETo analyze the clinical value of 24-hour urinary sodium determination in children with postural tachycardia syndrome (POTS).

METHODFifty-eight POTS children and 10 healthy children (control group) from Peking University First Hospital during June 2012 to May 2014 were enrolled. Their 24-hour urinary sodium and plasma sodium levels were compared. Correlation analysis was done between 24-hour urinary sodium and symptom scores in children with POTS. All patients were treated with oral rehydration salts. The POTS patients were divided into hyponatriuria group (urinary sodium < 124 mmol/24 h) and hypernatriuria group (urinary sodium ≥ 124 mmol/24 h). Kaplan-Meier curve was used to analyze the effects of different 24-hour urinary sodium levels in children with POTS receiving rehydration salts therapy.

RESULTThe 24-hour urinary sodium levels of children with POTS were significantly lower than that of control group ((110. 0 ± 45. 8) vs. (221. 3 ± 103. 6) mmol/24 h, t =3. 339, P = 0. 008), while no statistical significance was found in plasma sodium between the two groups ((139. 7 ± 2. 1) vs. (139. 7 ± 2. 3) mmol/L, t = 0. 082, P = 0. 935). Pearson correlation analysis showed that 24-hour urinary sodium and severity of symptoms in children patients were negatively correlated (r = - 0. 654, P < 0. 001) . Urinary sodium < 124 mmol/24 h was used as the cut-off value, there were 43 cases in hyponatriuria group and 15 cases in hypernatriuria group. The symptom scores were significantly higher in hyponatriuria group (10. 2 ± 3. 7 vs. 5. 0 ± 1. 8, P < 0. 001), there was no significant difference in other basic information and hemodynamic data between groups (P > 0. 05). Logistic regression analysis revealed that urine sodium < 124 mmol/24 h was independent risk factor for effectiveness of rehydration salts in POTS patients (OR = 0. 043, 95% CI:0. 004 - 0. 499, P = 0. 012). Kaplan-Meier survival analysis showed the long-term effect of patients receiving oral rehydration salts in hyponatriuria group was significantly better than that in hypernatriuria group (86. 0 % vs. 60. 0%, χ2 = 8. 471, P = 0. 004).

CONCLUSIONTwenty-four hours urinary sodium is a good indicaor for guiding children with POTS receiving rehydration salts therapy.

Case-Control Studies ; Child ; Fluid Therapy ; Hemodynamics ; Humans ; Postural Orthostatic Tachycardia Syndrome ; urine ; Rehydration Solutions ; Salts ; Sodium ; urine